Knife blade switch



Dec. 2, 1952 w. J. LEWIS 2,620,415

KNIFE BLADE SWITCH Filed May 4, 1949 l3 l2 INSULATION 14' FIG. 4 F165 [nvenlor M225 J LEWIS Patented Dec. 2, 1952 KNIFE BLADE swrrcn Warren J. Lewis, Mansfield, Ohio, assignor to The OhioBrass Company, Mansfield, Ohio, a corporation of New Jersey Application May 4, 1949, Serial No. 91,369

This invention relates to knife blade switches adapted to close a circuit between terminal members to which conductors are attached;

One of the objects of this invention is to provide a switch with a pair of blades having. limited movement relative to each other and to the support for the blades and also to the means for actuating the blades to their open and closed positions.

Another object of this invention is to provide a pair of relatively movable blades and means associated with the blades constantly urging the blades spaced apart and having means to limit such spaced apart relation.

Another object is to provide a pair of blades so related and constructed that theirnormal or maximum spaced apart relation will be reduced when the blades enter the space between the jaws of a pair of spaced terminal members.

Still another object of my invention is to provide a switch with a pair of relatively movable spaced apart blades to enter the space between the jaws of a terminal member and resilient means associated with the blades to press the blades into contact with the jaws.

Another object is to provide a switch having a pair of normally spaced apart blades and a pair of fixed and spaced apart terminal members, the blades being supported entirely by the terminal members when the blades are connecting the terminal members. v Y

Another object is to provide a switch with a pair of normally spaced apart blades and a pair of fixed and spaced apart terminal members having spaced apart jaws, and which. blades are supported entirely by the support member and the stop member when the switch it open.

The nature and scope of my invention will be more fully understood from the following description in connection with the accompanying drawing, in which Fig. 1 is a top view of my switch in the closed position.

Fig. 2 is a side View in elevation of Fig. l with the operating handle broken away in part. a

Fig. 3 is a side view of one of the terminal members.

Fig. 4 is a partial section taken. on the line 4-4 of Fig. 1 showing the relationof .various parts when the switch is closed.

Fig. 5 is a partial section taken through the pivotal point of the blades when the switch is in the open position.

Fig. 6 is a partial section taken on the line 5 6 of Fig. 1.

In the preferred embodiment of my invention, I provide a base member I preferably of in sulating material and on which is securely mounted a pair of terminal members 2 in spaced relation.

13 Claims. (Cl.200-'152) Each terminal member 2 is providedwith a pair of spaced apart, rigid and projecting jaws 3-3 providing a space 5 therebetween. I prefer to make the jaws rigid with respect to each other so as to maintain the contact surfaces 4-4 in constant parallel relation not only on the individual terminals but on both terminals taken together. It is customary in most switches of the type herein described to provide terminals with jaws that will spring in respect to each other and with their entering edges somewhat closer so as to produce a tapered opening whereby the jaws will be moved apart at their opening when the blade is forced therebetween. I have found that switches of this latter construction do not provide the efiicient contact which may be obtained whereby the jaws are formed rigid and partially parallel relative to each other and the opening 5 of a fixed dimension throughout as will be later understood.

The terminals are each provided with a projecting stud 6 by means of which the terminals may be secured to the basal by means of the nut 1. Each terminal is also provided with an opening 8 and screws 9 by means of which conductors may be secured to the terminals.

Mounted upon the base i between the spaced apart terminals 2 is a support member [0 and projecting therethrough is stem H having a head [2 positioned in the base I.

The opening [3 in the base in which the head i2 is located is closed by means of a disc M of insulating material. This space I3 if so desired and also the space in which the nuts I are positioned may be filled with a, plastic insulating compound.

Pivotally mounted upon the support it and stem H are two parallel blades !5-l5'. Positioned between the blades and pivotally mounted on the stem II is a drive member I6 having projecting flanges I! in engageable relation with the edges of the blades I5--l5 bymeans of which the blades may be actuated simultaneously into and out of engagement with the terminal members 2 when the drive member 16 is operated by means of the insulatedhandle l3 forming a part of the drive member l6.

I The free or upper end E9 of the stem H is threaded and mounted thereon is the nut 2!) provided with an integrally formed flange 2|. The

members 29 and 2| form stop means and also ber- 0 is greater than the combining thickness of the two blades and the drive member by an amount shown by the space 22 (Fig. 5).

This space 22 when the blades are in their open position results from springs 23, interposed between the blades adjacent their ends, whereby the blades are constantly urged apart but limited by the flange 21 of the stop means.

It will be noted that the maximum spaced apart relation of the blades is established by the stop means 20-2l and the stop means is so adjusted that the upper and lower face of the blades are spaced apart an amount somewhat greater than the space 5 between the jaws 3-3 thereby making it necessary for the springs 23 to yield in order to permit the blades l5l5 to enter the space 5.

In Fig. 4 is shown the relation of the parts at their pivotal point when the switch blades are in their switch-closing position. Here it will be noted that the space 22 has been reduced and a space 24 now exists between the upper blade I5 and the flange 2 i. .It should also be noted that in Fig. 4 there is a slight space between the face of the support member l3 and the blade l,

in other words the blades in the closed position of the switch are free from engagement with the support member I!) and the stop means -2l.

The blades now are supported entirely, it may be said, by the terminal members 2 and since the springs 23 are pressing the blades into engagement with the inner faces 4 l' of the terminals and since the space 5 is of uniform width in each terminal and the faces dl of the terminals are parallel and mounted in proper alignment between the terminals the contact between the blades and the jaws 3-3 will be substantially 100%.

It should be noted particularly, from Figs. 4

and 5, that the blades l5l5' are free to move e toward and away from each other upon the stem ll controlled only by stop means and support member and the resilient and yieldable springs 23, the latter held in position with respect to the blades by the sockets.

The free mounting of the blades and drive member at the pivotal center when the switch is closed as shown in Fig. 4 avoids all stress upon the blades tending to warp or bend the same or throw them out of maximum surface contact with the jaws, and it might be said the blades float relative to each other.

The base portions 26 of the terminal members are positioned on and secured to the base I on opposite sides of the longitudinal plane a.--a through the support shaft ll.

Certain changes may be made in the disclosed constructions and other embodiments may be made without departing from the scope of my invention, therefore I Wish to be limited only by my claims.

I claim:

1. A switch of the character described comprising, a base of insulating material, a support member, a shaft disposed through the base and the support member and projecting therefrom, a pair of elongated spaced and parallel blades mounted on the support member and the shaft upon which the blades oscillate, a drive member interposed between the blades and arranged to pivot relative to the shaft, the drive member having means engaging the blades to move the blades in unison with the pivotal movements of the drive member, a handle secured to the drive member, stop means on the shaft to adjust and to limit the spacing of the blades, yielding means between the blades at their ends constantly urging the blades apart and'to normally contact with the said supporting member and the stop means respectively when the switch is open, spaced terminal members each having rigid spaced jaws to receive the ends of the blades and means to receive a conductor and to secure the terminal to the base, the spacing of the jaws being less than the normal spacing of the blades including the thickness of the blades whereby the blades are forced somewhat together and into engagement with the jaws when the switch is closed.

2. A switch of the character described comprising, a base member, a shaft mounted on the base and projecting therefrom, a pair of elongated spaced blades mounted on the shaft and adapted to turn thereon, separate means on the shaft positioned below and above the blades to be engaged by the blades, the means on one side of the blades being adjustable upon the shaft to determine the overall spacing of the blades, spring means at each end of the blades normally forcing them apart and into engagement with the said separate means when the switch is open, drive means mounted on the shaft to turn thereon and having means to engage the blades to move them to their open and closed positions, the drive means having a portion projecting between and of less thickness than the inner spacing of the blades and having means for operating the drive means, a pair of spaced terminals secured to the base member and each having a pair of spaced jaws to receive the ends of the blades in engagement with the jaws respectively, and spring means interposed between the blades adjacent to their ends to force the blades into engagement with the jaws when the switch is closed and to force the blades into engagement with the said separate means when the switch is open.

3. An electric switch of the character described comprising, a base member, a pair of spaced terminal members, each member adapted tobe secured to the base member and provided with means to receive a conductor and also having a pair of projecting jaws with spaced flat and parallel contact surfaces a pair of elongated spaced blades, means to pivotally mount the blades on the base member and limit the separation of the blades, drive means pivotally mounted between the blades and cooperating with the blades to rotate the blades, handle means secured to the drive means to actuate the drive means and force the blades into the space between the jaws, and spring means positioned between the blades at their ends to normally hold the blades in their extreme separation when the switch is open and permit the blades to yield when closing the switch.

4. A switch comprising in combination, a pair of terminal members spaced apart, means associated with each terminal member to receive a conductor, each terminal member having a pair of projecting jaws in spaced relation, bridging means to electrically connect to terminals comprising a pair of rigid blades in spaced and parallel relation and movable into the space between the jaws, resilient means positioned between the blades to press them into and hold them in engagement with the inner faces of the jaws when positioned between the jaws, means to pivotally support the blades intermediate the ends of the blades, means associated with said support means to adjustably limit the-spacing between said blades, and means associated with the supporting means and with the blades to simultaneously move the blades either into or out of engagement with the said jaws.

5. A switch as per claim 4 in which the means associated with the supporting means and with the blades intermediate the ends of the blades is located between the blades and is of less thickness than the space between the blades when the blades are positioned between the jaws.

6. A switch comprising in combination, a pair of stationary terminals each having a pair of spaced apart jaws with parallel inner faces, a pair of blades spaced apart in parallel relation, means spaced from said terminals on which the blades are pivotally mounted, resilient means positioned between the blades for biasing them apart without changing said parallel relation, means to limit the spreading of the blades when the switch is open, the said resilient means permitting the lessening of said spreading of the blades when the blades are positioned in the space between the jaws, and operating means positioned between the blades to pivot the blades into and out of connecting relation with the terminals, the width of the operating means not exceeding the space between the blades when the switch is closed and the operating means cooperating with both blades to actuate them simultaneously.

7. A switch comprising a pair of spaced apart stationary terminal members, a pair of switch blades movable relative to each other and to the terminal members to open and close the switch, resilient means positioned between the blades biasing them apart and into contact engagement with the terminal members when the switch is closed, means to pivotally support the blades and adj ustably limit their separation when the switch is open, and means associated with both blades to simultaneously pivot them to either their open or closed position.

8. A switch comprising a pair of spaced apart stationary terminal members with projecting means having parallel contact faces, a pair of parallelly disposed switch blades in spaced relation movable toward and away from each other and having parallel faces to engage the said contact faces to electrically connect the terminal members, resilient means associated with the blades to yieldingly control the spacing of the blades when the blades are in either their open or closed positions, a support on which the blades are pivotally mounted, said support being spaced from said terminal members, means on the support to limit the spread apart dimension of the blades, and means engageable and movable with the blades to actuate the blades into and out of engagement with the terminal members.

9. A switch of the character described comprising, a base of insulating material, a support member, a shaft disposed through the base and the support member and projecting therefrom, a pair of spaced apart blades mounted on the support member to oscillate on the shaft, a drive member interposed between the blades to pivot the blades in unison relative to the shaft, stop means on the shaft to adjust and to limit the spaced apart relation of the blades, yielding means between the blades constantly urging the blades apart and into engagement with the support member and stop means respectively when the switch is open, spaced terminals mounted upon the base each having spaced apart jaws to receive the blades and means to receive a conductor, the spacing of the jaws being less than the spacing between the adjacent faces of the support member and the stop means, the construction and relation of the support member and the stop means and the said jaws being 6 such that when the blades are positioned in the space between the jaws and in contact with the jaws the blades will be free of engagement with the said adjacent faces of the support member and the stop means.

:10. In a switch, in combination, a base of insulating material, a pair of spaced apart terminal members each with means to receive a conduct-or and having a pair of parallel contact faces with a base portion to be secured to the base of insulating material, a pair of parallel disposed switch blades in spaced relation and having faces adapted to engage the parallel faces on the terminal members, yielding means associated with the blades to bias them apart, and supporting means including a shaft associated with the base upon which the blades are pivotally mounted, means associated with the blades and with the supporting means to limit the maximum spread of the blades when the switch is open, means associated with the blades to limit the minimum spread of the blades, the said minimum spread being less than that of the blades when the switch is closed, means associated with the last said means to actuate the switch blades to the open and closed positions, the said base portion of the terminals positioned on opposite sides of and spaced from the vertical longitudinal plane extending through the vertical axis of the shaft, and means securing the said base portion of the terminals to the base of insulating material.

11. In a switch the combination of a shaft, a pair of spaced blades pivotally mounted on said shaft, resilient mean-s to normally urge said blades apart, and means on said shaft to adjustably limit the spacing between said blades.

12. In a switch the combination of a shaft, a pair of spaced blades pivotally mounted on said shaft and adapted to engage and electrically connect spaced terminal members, said blades being movable toward and apart from each other, resilient means to normally urge said blades apart, and means on and movable relative to said shaft to limit the maximum and minimum spacing between said blades.

13. In a switch the combination of a shaft, a pair of spaced blades pivotally mounted on said shaft and adapted to engage and electrically connect spaced terminals, resilient means to normally urge said blades apart, and drive means mounted on said shaft and projecting between said blades to pivot said blades about said shaft to terminal connecting and disconnecting position.

WARREN J. LEWIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 803,895 Graybill Nov. 7, 1905 11,236,567 Jobe Aug. 14, 1917 2,226,386 Ramsey Dec. 24, 1940 2,234,563 Kneass Mar. 11, 1941 FOREIGN PATENTS Number Country Date 16,762 Great Britain June 25, 1902 391,249 Great Britain Apr. 27, 1933 496,417 Great Britain Nov. 30, 1938 506,293 Great Britain May 25, 1939 643,542 Germany Apr. 10, 1937 

